Neighbors told 9NEWS that police were often called to the home. 9NEWS requested records about how many times police have been there, but the request was denied as the records are a part of the homicide investigation.

The Department of Human Services is conducting a "Child Fatality Review" for Campbell. Although she is not specifically named, documents say the department is looking into the death of a 10-year-old killed last week.

An investigation like this happens when human services becomes aware of what the state calls "an egregious incident of abuse," neglect, near fatality or fatality involving a child. In Campbell case, she was already known to social services before her death.

9NEWS is looking into the extent social services was involved in her life.

Monarch Montessori of Denver says Campbell just finished her fifth grade year at the school a few weeks ago. There are grief counselors available to students.